feat: add solutions to lc problems: No.1427,1428

solution/1400-1499/1427.Perform String Shifts/README.md

@@ -58,9 +58,9 @@
 
 **方法一：模拟**
 
-遍历 `shift`，累加（减）得到最终偏移量 $x$，取模后对字符串 `s` 进行左移或右移。
+我们不妨记字符串 $s$ 的长度为 $n$。接下来遍历数组 $shift$，累加得到最终的偏移量 $x$，然后将 $x$ 对 $n$ 取模，最终结果就是将 $s$ 的前 $n - x$ 个字符移动到末尾。
 
-时间复杂度 $O(n+m)$。其中 $n$ 为字符串 `s` 的长度，$m$ 为 `shift` 的长度。
+时间复杂度 $O(n + m)$，其中 $n$ 和 $m$ 分别是字符串 $s$ 的长度和数组 $shift$ 的长度。空间复杂度 $O(1)$。
 
 <!-- tabs:start -->
 
@@ -71,11 +71,7 @@
 ```python
 class Solution:
     def stringShift(self, s: str, shift: List[List[int]]) -> str:
-        x = 0
-        for a, b in shift:
-            if a == 0:
-                b = -b
-            x += b
+        x = sum((b if a else -b) for a, b in shift)
         x %= len(s)
         return s[-x:] + s[:-x]
 ```
@@ -90,7 +86,7 @@ class Solution {
         int x = 0;
         for (var e : shift) {
             if (e[0] == 0) {
-                e[1] = -e[1];
+                e[1] *= -1;
             }
             x += e[1];
         }
@@ -138,6 +134,22 @@ func stringShift(s string, shift [][]int) string {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function stringShift(s: string, shift: number[][]): string {
+    let x = 0;
+    for (const [a, b] of shift) {
+        x += a === 0 ? -b : b;
+    }
+    x %= s.length;
+    if (x < 0) {
+        x += s.length;
+    }
+    return s.slice(-x) + s.slice(0, -x);
+}
+```
+
 ### **...**
 
 ```

solution/1400-1499/1427.Perform String Shifts/README_EN.md

@@ -50,18 +50,20 @@
 
 ## Solutions
 
+**Solution 1: Simulation**
+
+We can denote the length of the string $s$ as $n$. Next, we traverse the array $shift$, accumulate to get the final offset $x$, then take $x$ modulo $n$, the final result is to move the first $n - x$ characters of $s$ to the end.
+
+The time complexity is $O(n + m)$, where $n$ and $m$ are the lengths of the string $s$ and the array $shift$ respectively. The space complexity is $O(1)$.
+
 <!-- tabs:start -->
 
 ### **Python3**
 
 ```python
 class Solution:
     def stringShift(self, s: str, shift: List[List[int]]) -> str:
-        x = 0
-        for a, b in shift:
-            if a == 0:
-                b = -b
-            x += b
+        x = sum((b if a else -b) for a, b in shift)
         x %= len(s)
         return s[-x:] + s[:-x]
 ```
@@ -74,7 +76,7 @@ class Solution {
         int x = 0;
         for (var e : shift) {
             if (e[0] == 0) {
-                e[1] = -e[1];
+                e[1] *= -1;
             }
             x += e[1];
         }
@@ -122,6 +124,22 @@ func stringShift(s string, shift [][]int) string {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function stringShift(s: string, shift: number[][]): string {
+    let x = 0;
+    for (const [a, b] of shift) {
+        x += a === 0 ? -b : b;
+    }
+    x %= s.length;
+    if (x < 0) {
+        x += s.length;
+    }
+    return s.slice(-x) + s.slice(0, -x);
+}
+```
+
 ### **...**
 
 ```

solution/1400-1499/1427.Perform String Shifts/Solution.java

@@ -1,14 +1,14 @@
-class Solution {
-    public String stringShift(String s, int[][] shift) {
-        int x = 0;
-        for (var e : shift) {
-            if (e[0] == 0) {
-                e[1] = -e[1];
-            }
-            x += e[1];
-        }
-        int n = s.length();
-        x = (x % n + n) % n;
-        return s.substring(n - x) + s.substring(0, n - x);
-    }
+class Solution {
+    public String stringShift(String s, int[][] shift) {
+        int x = 0;
+        for (var e : shift) {
+            if (e[0] == 0) {
+                e[1] *= -1;
+            }
+            x += e[1];
+        }
+        int n = s.length();
+        x = (x % n + n) % n;
+        return s.substring(n - x) + s.substring(0, n - x);
+    }
 }

solution/1400-1499/1427.Perform String Shifts/Solution.py

@@ -1,9 +1,5 @@
-class Solution:
-    def stringShift(self, s: str, shift: List[List[int]]) -> str:
-        x = 0
-        for a, b in shift:
-            if a == 0:
-                b = -b
-            x += b
-        x %= len(s)
-        return s[-x:] + s[:-x]
+class Solution:
+    def stringShift(self, s: str, shift: List[List[int]]) -> str:
+        x = sum((b if a else -b) for a, b in shift)
+        x %= len(s)
+        return s[-x:] + s[:-x]

solution/1400-1499/1427.Perform String Shifts/Solution.ts

@@ -0,0 +1,11 @@
+function stringShift(s: string, shift: number[][]): string {
+    let x = 0;
+    for (const [a, b] of shift) {
+        x += a === 0 ? -b : b;
+    }
+    x %= s.length;
+    if (x < 0) {
+        x += s.length;
+    }
+    return s.slice(-x) + s.slice(0, -x);
+}